In recent years, it is known a technology of controlling, for example, a load provided in a consumer or a dispersed power source provided in a consumer by an energy management apparatus (for example, HEMS: Home Energy Management System) provided in each consumer.
Examples of the dispersed power source may include a fuel cell unit including a fuel cell such as an SOFC (Solid Oxide Fuel Cell). Examples of the dispersed power source may include a power generation equipment that utilizes clean energy such as sunlight, wind power, or geothermy.
Meanwhile, a gas meter that measures the used amount of gas supplied to the consumer is provided at each consumer. The gas supplied to the consumer is used also in equipment other than the fuel cell unit (for example, a gas stove, a water heater, and floor heating).
Since the gas supplied to the consumer is never continuously used in the equipment other than the fuel cell unit, generally, gas leak is suspected when gas is continuously used.
Therefore, when gas is continuously used over a specific period or more, the gas meter has a function of stopping gas supply in order to check whether or not there is gas leak.
However, the fuel cell unit is highly likely to continuously use gas. In such a case, as described above, the gas meter stops gas supply when continuous use of gas lasts a specific period. That is, the gas supplied to the fuel cell unit may stop at an unpredictable timing. In this way, when the gas supply to the fuel cell unit stops at the unpredictable timing, decrease in output efficiency of the fuel cell unit or a failure of the fuel cell unit may occur.